var num = 6;

function swap(what)
{
	for(var i = 0; i < num; i++)
	{
		document.getElementById('swap'+i).style.display = 'none';
	}
	document.getElementById('swap'+what).style.display = 'block';
}

/*
var createStyle = document.createElement('style');
var createStyleProp = document.createTextNode('.hidden { display:none; }');
createStyle.appendChild(createStyleProp);
document.getElementsByTagName('head')[0].appendChild(createStyle);
*/


function swap_cover(ElementId, bg)
{
	el = document.getElementById(ElementId);
	el.style.backgroundImage = "url('"+ bg + "')"; 
	return false;
}